Liebert 8 Tons, 50 & 60Hz user manual Installation Considerations, Room Preparation, Min Max

Site Preparation and Installation

2.0SITE PREPARATION AND INSTALLATION

NOTE

Before installing unit, determine whether any building alterations are required to run piping, wiring, and duct work. Carefully follow all unit dimensional drawings and refer to the submittal engineering dimensional drawings of individual units for proper clearances.

2.1Installation Considerations

The evaporator unit is usually mounted above the suspended ceiling using field supplied threaded rods. Refer to Figure 1 for possible configurations. The condensing unit may be:

•Indoor Air-Cooled Centrifugal Fan Condensing Unit mounted remotely or close coupled to the evaporator in the ceiling space.

•Outdoor Air-Cooled Propeller Fan Condensing Unit.

•Indoor Water/Glycol-Cooled Condensing Unit, mounted remotely or close coupled to the evapora- tor.

Table 1	Application limits, evaporator and chilled-water units*
Input Voltage		Range of Return Air Conditions to Unit
Min	Max	Dry Bulb Temp.	Relative Humidity
-5%	+10%	65°F to 85°F	20% to 80%
		(18°C to 29°C)

*Unit will operate at these conditions but will not control to these extremes.

Table 2	Application limits, indoor and outdoor air-cooled condensing units
Input		Condensing Units	Entering Dry Bulb
Voltage			Air Temperature
Min	Max		Min	Max
-5%	+10%	Outdoor Prop Fan Condensing Unit	-30°F (-34°C)	120°F (49°C)
		Indoor Air-Cooled Centrifugal Condensing Unit	-20°F (-29°C)	115°F (46°C)

Table 3	Application limits, indoor water/glycol-cooled condensing units
Input Voltage		Entering Fluid Temperature
Min	Max	Min	Max
-5%	+10%	65°F (18.3°C) *	115°F (46°C)
*Operation	below 65°	F (18°C) may result in reduced	valve life and fluid noise.

2.1.1Room Preparation

The room should be well-insulated and must have a sealed vapor barrier. The vapor barrier in the ceiling and walls can be a polyethylene film. Paint on concrete walls and floors should be vapor resis- tant.

NOTE

The single most important requirement for maintaining environmental control in the conditioned room is the vapor barrier.

Outside or fresh air should be kept to a minimum when tight temperature and humidity control is required. Outside air adds to the cooling, heating, dehumidifying and humidifying loads of the site. Doors should be properly sealed to minimize leaks and should not contain ventilation grilles.

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